I put Shorai's in both our F658's before shipping them to New Zealand for Christmas. So now the question is what regulator should I install as I really like the weight saving, and where to get it. Don't want to shove this excellent thread off topic so I think I'll post up a sep[arate one for that question.

Really appreciate your effort, really intersting even more important enlightening.

Give me a day to see if I can find one of the many excellent regulator/rectifier manufactures willing to put on an oe direct replacement plug.

I'd also like to talk to a few engineers about series rather then shunt regulators, as that is one possible way to deal with rapid stator heat aging.

This isn't likely critical yet. Lost Rider, the owner of the Shorai I found to be so unbalanced has been the first to experience many F800GS problems. It will take time and a lot of cycling before these issues show up for others.

Lastly I think it wise to wait for some more data points on what charging voltages are being seen on K7X bikes, as NCD's post has given me pause.

Just for more data, the voltage was 14.11 at 2000 RPM, and 13.99 at 3000 RPM.

0.15 volts higher, but still the behavior I am used to seeing. If you ride like I do, rarely idling, this is a voltage range that will cause issues with Shorai batteries unless you change the voltage regulator or use a balance charger every month or two.

I thought I might be loosing my mind, but looks like NCD's bike has a BMW test regulator in it or for whatever other reason is an outlier.

Either way, it is ALWAYS a good idea to check idle and mid RPM voltage on your individual motorcycles before making decisions.

Mike C. I think your old, cheap, and shitty Digitech meter might be more accurate then your Amprobe LOL, though the Amprobe sure is cute and accurate enough for most things. 13.84 volts is normally what I see at 3,000 RPM and it has seemed consistent across all the F8's I have measured.

Lower voltage at higher RPM when the alternator isn't fully loaded isn't odd, its wrong. Without getting overly technical, the R/R BMW selected for these bikes is quick to sense and slow to adjust. It should be ignoring the peaks and shooting for an average RMS voltage of, well 14.4 volts in my book, but 14.1 if BMW was thinking the bike was going to be released with a gel battery. What happens with this R/R is it senses the peaks (harmless, actually beneficial) and drives down the RMS average to keep the peaks around 14.1 volts. It's a design flaw or at least a mismatch of regulator to charging system with a lot of electrical noise.

Apostolos thank you.

ebrabaek, I still want to see what you measure, partially for another data point, but more because I am curious what kind of meter you use :)

Mike C. From tests I have now done with two Shorai LFX18 batteries, doing something seems warranted. Balance charging every couple of months will suffice and would be the cheapest solution, or replace R/R's.

I am still waiting for 3 R/R manufactures to get back to me. I talked to sales support at all 3 companies but what I need to speak to is an engineer for each. Took a bit to confuse each companies tech support and convince then I really did need an engineer and that allowing me at one would only take up 15 minutes of their time and could be profitable. Will update on what kind of a regulator will work best as well as exploring series regulators as soon as I learn something more.

Thanks all, finally got back my high current and accurate clamp from repair and calibration since my shunts demise, more on cranking, pulse, CA, and CCA soon, and expecting to receive an AntiGravity battery and toss it into the mix of tests soon.